Measurement of attitudes of trainee professionals to people with disabilities.
The SADP and IDMS attitude surveys are not fit for measuring staff attitude change.
01Research in Context
What this study did
The authors gave two paper surveys to trainee professionals. The surveys were the SADP and the IDMS. These tools claim to measure attitudes toward people with intellectual disabilities.
The trainees were in their first or final year of study. The team wanted to see if the surveys could spot attitude changes after training.
What they found
The surveys failed. Scores looked the same for first-year and final-year students. The tools also showed weak math marks for reliability and validity.
In plain words, the surveys could not tell if training shifted attitudes.
How this fits with other research
Lindsay et al. (2004) later showed the IDMS works fine when adolescents with mild ID answer it. This extends the 1995 paper: the tool is sound for clients, just not for trainees.
Vassos et al. (2023) reviewed mental-health scales for adults with ID. Their wide search did not praise the SADP or IDMS either. This synthesis includes the same scales and agrees they lack proof.
Drijver et al. (2025) built a new adaptive-behavior tool that passed every psych test. Their success shows that good ID measures are possible, making the 1995 flop look worse.
Why it matters
If you run staff training, do not use SADP or IDMS to prove it worked. Pick tools tested on staff, not clients. Track behavior like respectful language or person-centered plans instead.
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02At a glance
03Original abstract
The importance of measuring attitudes of trainee professionals to people with disabilities was addressed. A questionnaire which included the Scale of Attitudes toward Disabled Persons (SADP) and the Intellectual Disability Misconceptions Scale (IDMS) was completed by first and final year tertiary students enrolled in a 3-year course on intellectual disability. The attitude measures did not discriminate between the two groups of students, psychometric properties were poor and the factor structure of the SADP did not replicate previous findings. As expected, there was some convergence between the two attitude measures, and relationships to subject variables were consistent with previous research. Recommendations for subsequent research were discussed.
Journal of intellectual disability research : JIDR, 1995 · doi:10.1111/j.1365-2788.1995.tb00517.x